JPS62295068A - Resin for electrostatic charge image developing toner - Google Patents

Abstract

PURPOSE:To provide a titled resin suitable for heat roller fixing by using a partially crosslinked type polyester resin which has specific properties and is produced under specific conditions. CONSTITUTION:A trivalent or tetravalent carboxylic acid or the anhydride thereof or the mixture composed thereof of the amt. corresponding to 0.05-0.25mol per mol of a dicarboxylic acid unit (A) is brought into reaction with a polyester (I) of <=5,000 number average mol.wt. constituted of the dicarboxylic acid unit (A) and glycol unit (B) to form a branched polyester polymer (II). The branched polyester polymer (II) is then brought into reaction with a polyepoxide having >=5 epoxy groups in one molecule of the amt. corresponding to 0.03-0.3mol in terms of the epoxy group per mol of the carboxylic acid unit (A). The resin for electrostatic charge image developing toner having <=4,000 number average mol.wt., <=40mgKOH/g total of acid value and hydroxyl group value, 50-70 deg.C glass transition temp. and 100-200 deg.C softening point is thus obtd.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention 1. Industrial Application Fields 1. The present invention relates to electrostatic image developing toners, ) or 1. More specifically, electrostatic photography, electrostatic printing, etc. Part 1 Method 1 - Flute 1 used for heat roller fixing used to phenomenon electrostatic charge latent images formed in static hanging recording method etc.
Regarding fat.

[Prior Art] In image forming methods such as Shigeko photography and electrostatic recording, the toner image visualized in the development process is once transferred to transfer paper or other support and then fixed by a heat roller fixing method. This heat roller fixing method is excellent in that it has high thermal efficiency, and is especially capable of high-speed fixing, making it suitable for high-speed copying and other types of fixing.

However, with the development of the information society in recent years, demands for higher image quality, faster recording speed, and long-term preservation of records have increased in the fields of electrophotography, electrostatic stamps, and electrostatic recording.
There is a growing demand for improvements in the properties of 1 to 1 toners used in the development of electrostatic latent images. Improvements in such properties are also required for heat roller fixing toners, and for this reason, research has been carried out on various toner resins in order to meet the above-mentioned required properties with resins used in the i-toner. It's here.

For example, it is known that polyester resin can be used for heat roller fixing in Japanese Patent Publication No. 52-25420 and No. 5
No. 3-17496, No. 55-49305, Jimonsho 55-
No. 38524, No. 57-37353, No. 58-119
No. 52 and other publications, the polyesters and resins for toners that have been proposed so far all have advantages and disadvantages, and no one has yet been found that fully satisfies the requirements for improving the above characteristics. In other words, with polyester resin, it is easy to set the minimum fixing temperature.
It has the advantage of being able to cope with higher speed copying machines and reducing power consumption. In addition, when polyester resin is melted, it has good wettability to toner additives and supports such as transfer paper, making it easy to disperse carbon black, colorants, magnetic powder, charge control agents, etc. Although it has some advantages, such as being sexually resistant, it also has problems that are unacceptable for toner resins, as described in the next section.

(1) Resistance to plasticizers, etc. for vinyl chloride resin (hereinafter referred to as plasticizer resistance) is low, so the object to be copied may be an article made of soft vinyl chloride that contains a plasticizer (for example, an elliptical shape covered with soft vinyl chloride, etc.) ), the toner may contaminate the article or adhere to the article, and when the toner is peeled off, the toner may be damaged.

(2) Hot offset tends to occur, and in order to improve this, it is necessary to cross-link polynisful using a polycarbonate. Low-temperature fixation
! Not only is it difficult to produce toner, but also the dispersibility of carbon and dye is poor during the toner production process, making it difficult to produce toner.

(3) Since the amount of water adsorbed on the surface of the polyester resin is large, the amount of charge of the toner decreases under conditions of high temperature and high humidity, resulting in a decrease in image visibility and background smearing.

] Invention, iJ? Problems to be Solved] The present invention (is
The purpose is to solve the problems (1) to (3) above and to provide a heat roller fixing device that satisfies the above-mentioned required characteristics as completely as possible. It was discovered that a partially cross-linked polyester resin having a P'l of 100% satisfies the above object, leading to the completion of the present invention.

[Means for solving the problem] According to the present invention, (i) dicarboxylic acid units (A> and glycol units (B))
consisting essentially of (a>at least 80 mol% of dicarboxylic acid units (A>)
is an aromatic dicarboxylic acid unit, at least 30 mol % of the aromatic dicarboxylic acid units are prephthalic acid units and the remainder is isophthalic acid units, and (b) at least 80 mol % of the glycol units (B) are A polyester consisting of symmetrical glycol units, at least 30 mol% of the symmetrical glycol units being ethylene glycol units, and therefore having an average molecular weight of not more than 5000 (i>, f?A>0° per mole in the above dicarboxylic acid) 05 to 0.25 mol of the trivalent or 4illTl carboxylate or anhydride thereof or a mixture thereof is reacted to form a branched polyester polymer (II), Combine (ff),
5 in 1 molecule in an amount equivalent to 0.03 to 0.3 mol in terms of epoxy group per 1 mol of the carboxylic unit (A).
reacting with a polyepoxide having an epoxy group of more than 100%, resulting in a number average molecular ff of less than 14000,
The total of acid value and hydroxyl value is 40mffKOH/! 9 or less,
A resin (for electrostatic image phenomenon toner) having a glass transition temperature of 50 to 70°C and a softening point (according to the ring and ball method) of 100 to 200°C is provided.

The present invention will be explained in detail below.

The polyester inorganic material (1), which is the base of the toner resin of the present invention, is substantially composed of dicarboxylic acid units (A>) and glycol units <B>.

At least 80 mol%, preferably 90 mol% of the dicarboxylic acid units (A) constituting the polyester polymer (1)
~100 mol% are aromatic dicarboxylic acid units, and at least 30 mol% of the aromatic dicarboxylic acid units,
It is important that preferably 50 mol% or more is occupied by terephthalic acid units, with the remainder consisting of isophthalic acid units.

If the proportion of the aromatic dicarboxylic mono(V) in the dicarboxylic acid unit is less than 80 mol%, the final 1d
(ff Dioctyl phthalate (hereinafter referred to as DOP)
) and dibutyl phthalate (hereinafter referred to as DBP)
It can be seen that there is a tendency for the resistance to plasticizers such as, etc. and the caking property to decrease.

When the proportion of terephthalic acid units in the aromatic dicarboxylic acid units is lower than 30 mol%, the crystallinity of the resulting polyester polymer is relaxed and the high-temperature offset resistance is good, but the plasticizer properties and There is a tendency for storage stability etc. to decrease, making it difficult to obtain a resin with well-balanced properties.

The above polyester can contain aliphatic dicarboxylic acid units in a proportion of 20 moles or less of dicarboxylic acid units if necessary, so that the polyester of the present invention can be formed using the resin. However, if the ratio of aliphatic dicarboxylic acid units increases, the resulting resin's resistance to plasticizers such as DOP and DBP and its caking resistance may be improved. There is a tendency for sexual performance to decline. Examples of aliphatic dicarboxylic acid units that can be used include one or more units derived from aliphatic dicarboxylic acids such as succinic acid, maleic acid, fumaric acid, adipic acid, and hydrogenated phthalic acid. .

Glycol unit (B
) is also important, and in the present invention, it is necessary that at least 80 mol% of the glycol units (B) be symmetric 1 raw glycolyl units. Symmetry [When the proportion of raw glycol units is less than 80 mol%, the crystallinity of the obtained polyester polymer is relaxed and the high temperature resistance
[While the raw properties are good, plasticizer resistance, storage stability, etc. tend to deteriorate around the first grade, which is undesirable because it becomes difficult to obtain a resin with a good balance in these properties.

Examples of the symmetrical raw glycoyl unit include ethylene glycol, 1,3-propylene glycol, 1,4-butylene glycol, neopentyl glycol, 1,6-
Alkylene glycols such as hexanediol; polyalkylene glycols such as diethylene glycol, triethylene glycol, polyethylene glycol, and polypentamethylene glycol; 1,4-dimethylolbenzene,
1° 4-Cyclohexane dimetatool, hisphenol A, hydrogenated bisphenol △, bisphenol-ethylene oxide adduct, etc. One type bb< includes more than one unit.

In addition, in the present invention, it is important that at least 30 mol% of the symmetric glycol units are ethylene glycol units, and if the content of the ethylene glycol units is less than 30 mol%, DOP, DBP, etc. However, there are disadvantages such as low resistance to plasticizers, low resistance to λ11, and decreased storage stability. It is preferable that the amount of lamb is 1, 21, or 40 moles or more, 16 or more of the symmetrical glycol units.

In addition, the polyester polymer used in the present invention (
I) may contain an asymmetric glycol unit, if necessary, for the purpose of further improving physical properties such as low-temperature fixability and abrasion resistance of the resin of the present invention. Such asymmetric glycol units include, for example, 1,2-propylene glycol, 1,2-butylene glycol, 1,
One or more units derived from 3-butylene glycol, polypropylene glycol, etc. are included. However, if the content of these asymmetric glycol units is higher than necessary, physical properties such as plasticizer resistance and storage stability of the final resin tend to decrease.
The content of the asymmetric glycol unit should be kept at 20 mol% or less of the glycol unit (B), preferably 10 mol% or less.

The polyester polymer (technique) having the above-mentioned sticky structure includes a dicarboxylic acid corresponding to the dicarboxylic acid unit described above or an ester-forming derivative thereof (for example, a halide, a lower alkyl ester, a phenyl ester, etc.),
The glycol corresponding to the glycol unit or its ester-forming derivative (eg, ester with a lower carboxylic acid) can be prepared by a condensation polymerization method known per se.

The polyester polymer (I> is a number average molecular weight of 5000 or less, preferably 3500 or less, and the number average molecular weight a
If it exceeds 5,000, the fixing properties of the finally obtained toner will deteriorate. To prepare a polyester polymer (■) with a number average molecular weight of 5,000 or less @9, a small amount of the above-mentioned dicarboxylic acid unit (, A, > or glycol unit (B) is added as a molecular weight regulator to the polyester polymer in the polymer phase). , polyester polymers (I>) can also be obtained.

According to the present invention, the above-mentioned polyester polymer (1
) is 0.0 per 1 mole of the dicarboxylic empty unit (A)
3 (IIIi'b) of the product equivalent to 5 to 0.25 moles
L, < is a branched polyester polymer obtained by reacting a tetravalent carboxylic acid, its anhydride, or a mixture thereof (
n). The trivalent or 4 fl[i carboxylic acid (hereinafter referred to as each carboxylic acid) that can be reacted with the polymer (I>) may be of either aliphatic type or aromatic type; Examples of such carboxylic acids include 1,2,4-butanetricarboxylic acid,
Aliphatic polycarboxylic acids such as 1,2.4-cyclohexanetricarboxylic acid, trimellitic acid, pyromellitic acid, pyromellitic acid monomethyl ester, naphthalenetricarboxylic acid, naphthalenetetracarboxylic acid, hensifenonetetracarboxylic acid These polycarboxylic acids can be used alone or as a mixture of two or more.Also, these polyhydric carboxylic acids can be used in the form of acid anhydrides. may be reacted with the polyester polymer (I>).

In addition, the amount of polyhydric carboxylic acid or its acid anhydride to be used for the polyester polymer (I> is 0.05 to 0.25 per mole of dicarboxylic acid unit (A) in the polymer (I>).
mol, preferably in the range of 0.05 to 0.15 mol.

Here, if the amount of polymedullary carboxylic acid or its acid anhydride is less than 0.05 mol per 1 mol of the dicarboxylic acid unit (A), high-temperature offset of the final toner is likely to occur, and the fixable temperature The width (temperature range in which low-temperature offset and high-temperature offset do not occur) becomes narrow, making it impossible to put it to practical use as a toner. On the other hand, if the amount of polyhydric carboxylic acid or its acid anhydride is more than 0.25 mol, +S
Although the temperature range at which the toner can be fixed is widened, the acid value of the final resin becomes too high, making it easier for moisture to be adsorbed on the surface of the toner particles, resulting in a decrease in image density and fogging at high temperatures and high humidity. , the dirt becomes like a cow.

Branched polyester polymer modified with polyhydric carboxylic acid as described above <n> 4 at t, t, f+2
000 or less, preferably 3000 or less, and an acid value of 40 mFKOH/'9 or less. Furthermore, from the viewpoint of low temperature fixing properties and storage stability of the toner resin of the present invention, the polyester polymer (II) is generally at least 50°C, preferably 50°C.
It is desirable to have a glass transition temperature (Tq>) within the range of 5 to 65°C.

The polyester polymer (n) has a carboxyl group introduced by reaction with a polyhydric carboxylic acid or its core anhydride, and a carboxyl group introduced by reaction with a polyepoxide having 5 or more epoxy groups in one molecule. Partially cross-linked.

The polyepoxide used as a crosslinking agent contains 5 in 1 molecule.
If the number of epoxy groups in one molecule of polyepoxide is less than 5, the final polyester resin will have less branching.
In order to obtain a resin with sufficient non-offset properties, a large number of epoxy compounds are required, which not only deteriorates the fixing properties of the resulting toner, but also deteriorates the dispersibility of carbon, dyes, etc.; and 4) Magnetism. decreases, and toner manufacturability deteriorates.

However, when partially crosslinking the polyester polymer (II), even when using a polyepoxide having fewer than 5 epoxy groups in one molecule, the polyester polymer (1) is converted into a branched polyester (II). By using a large amount of polyhydric carboxylic acid or its anhydride (2) beyond the scope of the present invention, a toner having a wide visible temperature range can be obtained. As mentioned above, when the temperature is high and the humidity is high, image density decreases, fogging, background smearing, etc. occur. In other words, the purpose of the present invention is to obtain 1 q of excellent toner that has a wide fixable temperature range, exhibits a small decrease in image density even at high temperatures and high humidity, and does not cause gagginess, using polyester polymer (II). Partial crosslinking was made possible by using a polyepoxide having five or more epoxy groups in one molecule.

Specific examples of the above-mentioned polyepoxides include ○-talesol novolac type epoxy resin, phenol novolac type epoxy resin, partially epoxidized polybutadiene, epoxidized resorcinol-acetone condensate, vinyl polymer having an epoxy group, or These include vinyl copolymers and polyfunctional epoxy compounds partially reacted with acids, amines, etc.

The ratio of polyepoxide to the polyester polymer (II) can be varied over a wide range depending on the type of polyepoxide used and the desired degree of crosslinking. I
) in the dicarboxylic acid unit (A>, based on the foot of the unit (A), 0.03 to 0 in terms of epoxy group per 1 mole of the unit (A)
．． It is advantageous to use within an amount corresponding to 3, preferably 0.05 to 0.1.

In this crosslinking reaction, the softening point of the resulting resin of the present invention is 100.
It can be carried out until the temperature is within the range of ~200°C, preferably 120~190°C.

Further, the resin of the present invention prepared as described above has a number average molecular weight of 4000 or less, preferably 3500 or less, and a sum of ul+lfi and water Mu value of 40myKOt-
f/h or less, glass transition temperature (TCI) is 50-70℃
can be within the range of

By the way, the term "averaged molecule matrix" used in this specification refers to gel permeation chromatography (Gel permeation chromatography).
1Af using polystyrene standards by PC)
It means the value calculated by cutting out the a-line.
"Glass transition temperature" (TCI) is a differential scanning calorimeter (
The intersection point between the extension line of the low-temperature side baseline and the tangent to the endothermic part according to DSC>. Also, the softening point is J Is-
It was measured by the ring and ball method described in 2207.

Production of i~lunar using the resin of the present invention can be carried out according to a method known per se, and usually
When blending a coloring agent and, if necessary, 1) a property improving agent with the fat to make a magnetic toner,
A retoner can be produced by combining the magnetic 14 powder instead of the coloring agent, thoroughly melting and kneading, and grinding.

When preparing the toner as described above, in addition to the resin of the present invention as a binder, the resin 100 of the present invention may be added to a range that does not significantly affect the effects of the resin, for example, the resin 100 of the present invention.
Other stone control ability with a funeral of 30 ω parts or less per hand part, 19
1 [For example, polyester resins other than those of the present invention and other resins generally used for heat roller fixing may be used in combination.

Coloring agents include carphone black, nigrosine dye (
C,1,NQ50415B>, Aniline Blue (C,
1, Nα50405>, Calco oil blue (C, I
, No, azocc Blue 3), Chrome Yellow (C,1,NQI4090), Ultramarine Blue (C,1,Nα77103), DuPont Oil Red (C,1,No,26105>, Quinoline Yellow (C,1,Nα47005) >, Methylene Blue Taloride (C, 1, Nα52015), Phthalocyanine Blue (C, 1, Nα 74160), Malachite Green Off 1 Narate (C, 1, No, 42000), Lamp Black (C, 1, No, 77266>, Rose Bengal (C, 1, No. 45435), mixtures thereof, etc. These colorants can be used with sufficient a
It is necessary to contain the resin in a sufficient proportion to form a visible image of 100% of the binder, and the ratio is usually 1 to 20 parts per 100 parts of the binder.

The magnetic material may be a metal or alloy that exhibits ferromagnetism, such as ferrite, magnetite, iron, cobalt, or nickel, or a compound containing these elements, or a material that does not contain a ferromagnetic element but can be prepared by subjecting it to appropriate heat treatment. Mention may be made of alloys which become ferromagnetic, such as alloys of the type called Heusler alloys containing manganese and copper, such as manganese-copper-aluminum, manganese-copper-tin, or chromium chloride, among others. . These nutrients are uniformly dispersed in the binder in the form of a fine powder with an average particle size of 0.1 to 1 micron. The content thereof can generally be 20 to 70 parts by weight, preferably 40 to 70 parts by weight per 100 parts by weight of toner.

In addition, in the toner prepared using the resin of the present invention, as a property improver, substances having mold release properties, such as higher fatty acids or metal salts of higher fatty acids, may optionally be used for the purpose of further improving anti-offset properties. , natural or synthetic waxes, higher fatty acid esters or partially saponified products thereof, alkylene bis fatty acid amides, fluorinated fats,
A silicone resin or the like may also be blended. The blending amount can generally be 1 to 10 parts by weight per 100 parts by weight of the binder.

[Example] Next, the present invention will be further explained by examples.

In addition, unless otherwise specified, "1 part" in the examples and the blending ratio of each component are parts by weight.

Example 1 311 parts of dimethyl terephthalate, 78 parts of dimethyl isophthalate, 114 parts of ethylene glycol, 111 parts of hydrogenated hisphenol A, 1.4 parts of tetrabutyl titanate G
: Added to a four-necked round-bottomed flask fitted with a thermometer, a stainless steel tube, a glass nitrogen inlet tube, and a flow-down condenser. Next, the temperature was heated under a nitrogen atmosphere, and the reaction temperature was gradually raised while removing methanol produced by the transesterification reaction, and kept at 240°C to complete the transesterification and convert the polyester (I> 17. This polyester (I
> is di-sulfonic acid unit <A) of 100 mol% of aromatic dicarboxylic acid units consisting of 80 mol% of terephthalic units and 20 mol% of isophthalic acid units, and 80 mol% of ethylene glycol units.
0 mole? 6 and 20 mol% of hydrogenated bisphenol A.
) and had a number average molecular weight of 1500.

38 parts of trimellitic anhydride (
0.1 mol per 1 mol of the above carboxylic acid unit (A)) was added and reacted at 240°C for 4 hours to obtain a small branched polyester aggregate (n).

Next, this polyester (II>) was added with ortho-creso-/lenovolac type epoxy resin 253 having an average of 8.5 epoxy groups in one molecule (0.00% as epoxy group per mole of self-carboxylic acid unit (A)). 06 mol) was added, the reaction was carried out at 250-260°C for 1 hour, and r
l oil 51ng K OH, %'j, hydroxyl group 1i11i
32m3KOl-1/'; i, number average molecule 22600
A polyester for toner having a glass transition temperature of 62°C and a softening point of 170°C was produced.

100 parts of the polyester resin for toner obtained above, carbon black (manufactured by Mitsubishi Chemical Industries, Ltd. MA-100>5
After premixing 2 parts of a charge control agent (Hontron 5-34 manufactured by Orient Chemical Co., Ltd.) using a Henschel mixer, the mixture was melted and kneaded using a twin-screw extruder, cooled, and finely ground using a jet mill. Classified with a classifier and average particle size 12
A toner of ~13μ was obtained. This polyester resin for toner had good dispersibility of the charge control agent and carbon black, good pulverizability during toner production, and was excellent in manufacturability.

A developer was prepared by mixing 90 parts of a ferrite carrier (F-100 manufactured by Nippon Tetsuko Co., Ltd.) with 10 parts of this toner. When the toner properties of the toner and developer obtained above were evaluated according to the test method below, it was found that the lower limit of fixing temperature was as low as 160°C, yet the offset generation temperature was extremely high as 240°C, and that it was excellent over a wide range of fixing temperatures. It was toner. Furthermore, the storage stability and plasticizer resistance showed very good results with no abnormalities observed. Furthermore, the amount of charge on toner at normal temperature and humidity is
19.8μC/9, while the charge amount of the toner at high temperature and high humidity was 17.8μC/3, showing stable charging characteristics with no significant decrease in charge amount, and improving image quality. The image temperature also showed a small decrease in image temperature, and the image quality was F or better, with no defects such as background stains (rating ○). - (1) Lower limit fixing temperature and offset occurrence temperature An electrostatic charge image formed by a normal electrophotographic method using an electrophotographic copy volume DC-191 manufactured by Mita Kogyo Co., Ltd. is washed with the above developer,
The toner image was transferred onto plain paper. The transfer paper on which this toner acid has been formed is made of a heat roller whose surface layer is made of Teflon and a pressure roller made of silicone rubber, and the pressure between the rollers is 20.
Using a fixing device with a paper feed speed of 250 mm and a second, fixing was carried out by varying the temperature of the fixing roll,
The fixation lower limit temperature and Offsera 1-Hikari temperature were measured.

(2) Storage stability Put 100g of toner in a cylindrical container with a diameter of 6cm,
After being left for one week in an atmosphere at .degree. C., blocking and caking of the toner particles were carefully observed, and storage stability was evaluated using the following evaluation criteria.

○ Phenomena such as niblocking and caking do not occur at all, and almost no change is observed in fluidity.

Δ: Slight blocking occurs or the container is easily loosened by shaking, and fluidity is restored. No practical problems.

×: Caking occurs, and even if the container is shaken, the caking particles do not loosen and remain as souls.

(3) Place plasticizer-resistant toner 2-position in DOP and DBP, respectively, and
The state of the particles was carefully observed after 24 hours at °C, and the next δT
"+" indicates plasticizer resistance by h·r11!J'i.

O: No change was observed, showing poor plasticizer resistance.

Δ: 1 to 4112 particles cause blocking, but do not become soft and are not a problem in practice.

X: The toner particles are swollen or partially dissolved, causing a blocking phenomenon, and the particles are softened.

(4) Charge amount and image 1 raw developer at high temperature and high humidity: 20°C - 55% relative humidity, which corresponds to normal temperature and normal humidity; C-Stir at 85% relative humidity for 3 hours each to determine the charge amount of the toner (
Expressed as μC/'7) is manufactured by Toshiba Chemical Corporation blow-off)'! Charge body: () Coulometric measurement (Measurement was made using a TB-200 machine, and the difference in the amount of charge was compared.) Also, regarding image quality, the above developer was used and the test method (1) was used. Perform image development and compare one image at 20°C and 65% relative humidity with one image at 35°C and 85% relative humidity,
The image depth difference and the degree of background smudge were evaluated using the following criteria (15 criteria).

○: 20°C - phase ^, 1 part ratio of 1tξ to 3 at 65%
Art dealer IJL image 1 at 5°C - relative humidity 85%) The decrease in seismic intensity is small, probably due to dirt! 11-I.

△: 20°C - Humidity [Compared to the image taken at Banquet 659'O, the image at 35°C - 85% relative humidity shows a decrease in image density, but there is no background staining, and it is within the range of practicality. It is within.

X: 20°C - 35°C compared to the image at 65% relative humidity
An image at a relative humidity of 85% has a large decrease in image density and background smudges, making it unusable for practical use.

Examples 2 to 6 and Comparative Examples 1 to 3 Each of the polyester resins for toner was prepared in substantially the same manner as in Example 1 using the formulations shown in Table 1 below. I had HA.

In addition, in the amount of each compounded component in Table 1 below, 0
Of the numerical values shown, the polyester union (1) is expressed as mol%, and the polyester polymer (II) and polyepoxide are expressed as the molar ratio per mole of dicarboxylic acid unit of the polyester (I>). example,
The same applies to comparative examples).

(Left below) Toners were produced in the same manner as in Example 1 using the toner polyester resins of the Examples and Comparative Examples obtained above, and then the toner properties were evaluated, and the evaluation results are shown in Table 2.
It was shown to. Table 2 also shows the measurement results of the physical properties of the polyester polymer (I>) and the polyester resin for toner.

(The following is a blank space) As is clear from the table and results in Table 2 above, the toner of Example 2, which is the present invention, is an aromatic compound containing a relatively small proportion of terephthalic acid type (35 mol%). Since the polyester polymer (I) composed of dicarboxylic acid is used as the base polymer and is manufactured using the polyester resin for toner obtained from the base polymer, the plasticizer resistance and storage stability are as low as those of Examples. Although it was slightly inferior to toner 1, the offset generation temperature was 2.
The temperature was as high as 45°C, indicating good toner properties.

Furthermore, since polyepoxide having 8.5 epoxy groups in one molecule was used as a crosslinking agent, it exhibited excellent charging properties and imageability at high temperatures and high humidity.

In Example 3, the entire aromatic dicarboxylic acid in the polyester polymer (I) as the base polymer was composed of terephthalic acid, and the toner exhibited excellent toner properties with one layer of plasticizer resistance. Since polyepoxide having 5.2 epoxy groups in one molecule was used as a crosslinking agent, the toner had a small drop in charge foot at high temperature and high humidity, and had good image quality.

In Example 4, the proportion of ethylene glycol in the glycol component constituting the polyester polymer (I) was 35%.
Although there was a tendency for the toner's plasticizer resistance to slightly decrease, perhaps because it was relatively small (mol%), it was commercially available to the extent that it did not pose a practical problem, and the fixing lower limit temperature, nof set generation temperature, charge evacuation, and image quality, etc. [It was a toner with excellent performance.]

In Example 5, the glycol units constituting the polyester polymer (1) were the same as in Example 4, and the proportion of terephthalic acid units in the dicarboxylic acid component was relatively small at 35 mol%. Although the plasticizer resistance of the toner was slightly decreased, it was not to the extent that it impeded practical use, and other toner properties were good.

In Example 6, the proportion of symmetrical glycol in the glycol components forming the polyester polymer (I) was 85%.
Perhaps because the mol% was relatively low, the plasticizer resistance of the toner was slightly lowered, but it was not to the extent that it impeded practical use, and the other 1-toner properties were good.

On the other hand, in Comparative Example 1, the v1 group occupied by the aromatic dicarboxylic acid in the dicarboxylic acid component constituting the polyester polymer <I) was as much as 70 mol'3; In Comparative Example 3, the symmetric P [gjJ ratio of ethylene glycol in the glycol component was 20 mol%, both of which are outside the scope of the present invention, and the charging characteristics Although it showed relatively good results in terms of image quality and image quality, it had poor plasticizer resistance and was of no practical use.

Example 7 Dimethyl terephthalate 249 was placed in a reactor similar to Example 1.
parts (64 moles 96), 78 parts dimethyl isophthalate (2
0 mol%>, 99 parts of ethylene glycol<80 mol%,
However, in order to make the reaction proceed smoothly, an excess amount of ethylene glycol was used, and after the reaction was completed, the excess amount of ethylene glycol was removed by vacuum operation), hydrogenated bisphenol Δ96 parts (20 mol%), tetrabutyl titanate 1 ．．
4 parts were added, the temperature was raised under a nitrogen atmosphere, and while removing methanol produced by the transesterification reaction, the reaction temperature was gradually raised and maintained at 240°C to complete the transesterification reaction. 1/I for 30 minutes at 240°C.
After reducing the pressure to I/II H3 and carrying out a polycondensation reaction for another 1 hour, 31 parts (16 mol%) of dimethyl terephthalate was added and the reaction was further carried out for 1 hour to obtain a polyester (1) with a number average molecular weight of 34oo. Ta. Next, the above polyester (
To 1), 31 parts of trimellitic anhydride (0.08 mol per 1 mol of the above dicarboxylic acid unit (A)) was added at 240°C in a nitrogen atmosphere at normal pressure, and the reaction was carried out for 1 hour to form a polyester (
II>”1%.

To this polyester (II), Li=, 250-260
153 phenol novolac type epoxy resins having 8 epoxy groups with an average of 5.2 cycles in one molecule at 153° C. (0.53 as epoxy groups per mole of the above dicarboxylic acid unit (A)).
04 mol) was added and the reaction was carried out for 1 hour, resulting in 1lfi! Ii
25#ffKOH/';j, water [mWifu1OmgK
OH/q, number average molecular weight 3000, glass transition temperature 63
A polyester resin for toner with a softening point of 175°C was manufactured. Regarding this polyester for toner (cloudy (greasy), a toner special material was designed in the same manner as in Example 1.
Plasticizer resistance was evaluated with a Q mark, storage stability was evaluated with an O mark, the minimum fixing temperature was 165°C, the offset generation temperature was 240°C, and the rate of change in charging arsenic (L/N = 18.2/21. 2> was also as small as 0.85, indicating toner characteristics with excellent image quality.

Example 8 and Comparative Examples 4 to 7 Using the formulations shown in Table 3 below, Example 8, Comparative Examples 4 and 5 were prepared in substantially the same manner as Example 1, and Comparative Examples 6 and 7 were prepared in the same manner as in Example 1. Each polyester resin for toner was produced in substantially the same manner as in Example 7.

(Hereinafter, blank spaces) As described above, toners were produced in the same manner as in Example 1 using the polyester resins for toners of the Examples and Comparative Examples, and the toner characteristics were evaluated. The evaluation results are shown in Table-4. The results of measuring the physical properties of the polyester polymer (1) and the polyester resin for toner are also shown in Table 4.

(Margin below) As is clear from the results in Table 4 above, the toner of Example 8 has a minimum fixing temperature of 150°C and an offset generation temperature of 2.
At 50℃, the temperature difference between the two, that is, the fixable temperature is 10
0°C: It is a highly practical toner that is wide and dull and has excellent plasticizer resistance and storage stability. Furthermore, regarding the charge amount and image quality at high temperature and high humidity, the toner properties were within a range that did not impair practicality.

Comparative Example 4 was obtained because a dicarboxylic acid was used instead of a 3-4IIIi carboxylic acid or its acid anhydride when converting the polyester polymer (1) into a branched polyester polymer (n). Although the softening point of the polyester resin for toner is 205°C, which is far above the range of the present invention, the humidity at which offset occurs is as low as 220°C, and the fixable temperature range is narrow at 40'C. Ta.

In Comparative Example 5, when converting the polyester resin (I>) into a branched polyester polymer, trimellitic anhydride was used in a large amount of ○, 3 mol per mol of the dicarboxylic acid unit (A), which is outside the scope of the present invention. The resulting resin had an acid value of 45, a hydroxyl value of 5, and the sum of these values was 50, which was outside the scope of the present invention. However, the image density decreased and background smear occurred under high temperature and high humidity conditions, making it impractical.

Comparative Example 6.7 shows that when partially crosslinking polyester polymer (I[>) with polyepoxide, instead of crosslinking with polyepoxide having five or more epoxy groups in one molecule, Diglycidyl ether of bisphenol A having an epoxy group is added to the dicarboxylic acid unit (A
) per mole, respectively 0, 1.
It was crosslinked with 0.15 mol, and in Comparative Example 6, the offset generation temperature was as low as 230°C, and the lower limit fixing temperature was 175°C.
The average fixing temperature is 55°C, which is poor in practicality.On the other hand, in Comparative Example 7, although the offset generation temperature was high at 240°C, the minimum fixing temperature was high at 195°C, and the average fixing temperature was 45°C. °C, which is inferior to practical use, and the dispersion of carbon and charge control agent into the polyester resin is poor.
It required a long time of kneading to form a toner, and furthermore, the pulverization efficiency in a jet mill was low, and the toner SIJ had poor magnetism.

Example 9 65 parts of the polyester resin for toner prepared in Example 1, magnetite fine powder (Toda Kogyo WEPT-1000)
> 35 parts were treated in the same manner as in Example 1 to reduce the average particle size to 1.
A 2μ magnetic toner was produced.

The resulting toner is placed in an electrostatic charge generator equipped with a rotatable stainless steel sleeve with a magnet in the center and a doctor blade to charge the toner and form a uniform layer of magnetic toner on the sleeve. The electrostatic latent image on the support member was developed and transferred onto transfer paper, and then heat roll fixing was performed in the same manner as in Example 1.

This toner has good fluidity and forms a uniform toner layer on the stainless steel sleeve. It gave a fog-free image in bright light. Further, 10,000 copies were made continuously, but no change in image quality was observed. Furthermore, the storage stability of this toner was examined in the same manner as in Example 1, and no defects such as caking were observed.Although the same development process as described above was performed, no deterioration in image quality was observed. Ta.

Note that the lower limit temperature for fixing the toner in this example using a heat roll is 170°C, and the quality (offset generation) is 250°C.
It had extremely excellent temperature characteristics.

[Effects of the Invention] The toner resin provided by the present invention has (a) high resistance to plasticizers for vinyl chloride resins, and is resistant even when the copied object comes into contact with soft vinyl chloride articles containing plasticizers; , the object may become contaminated, or the object to be copied may stick to the object.

(b) Although the fixing temperature is low, it has a high offset occurrence temperature, and the offset phenomenon is difficult to occur because the fixing temperature is within the range.(C) Although the fixing temperature is low, It has good dispersibility in resins such as carbon and dyes, has good crushability, and has excellent toner %U formation properties.

(d) Good tribocharging, showing a stable charge amount during use, and in particular, the toner charge amount does not decrease even under high temperature and high humidity conditions, and image 1@ degree decrease and background smearing do not occur. Hateful.

It exhibits various excellent properties such as, and is suitably used as a binder for heat roller fixing type dry toner.

Claims (1)

[Claims] (i) Dicarboxylic acid unit (A) and glycol unit (B)
consisting essentially of (a) at least 80 mol% of dicarboxylic acid units (A);
or aromatic dicarboxylic acid units, at least 30 mol% of the aromatic dicarboxylic acid units are terephthalic acid units and the remainder are isophthalic acid units, and (b) at least 80 mol% of the glycol units (B) are A polyester (I) having a number average molecular weight of 5000 or less comprising symmetrical glycol units, in which at least 30 mol% of the symmetrical glycol units are ethylene glycol units,
0.05 to 0.0% per mole of the dicarboxylic acid unit (A).
reacting an amount equivalent to 25 moles of a trivalent or tetravalent carboxylic acid or its anhydride or a mixture thereof to obtain a branched polyester polymer (II); ) with a polyepoxide having 5 or more epoxy groups in one molecule in an amount equivalent to 0.03 to 0.3 mol in terms of epoxy groups per 1 mol of the carboxylic acid unit (A). A number average molecular weight of 4000 or less, a total of acid value and hydroxyl value of 40 mgKOH/g or less, a glass transition temperature of 50 to 70°C, and a softening point (according to the ring and ball method) of 1
00-200°C resin for electrostatic image developing toner.